1. Field of the Invention
The present invention relates to electronic equipment which with a pushbutton mounted on a panel thereof.
2. Description of the Related Art
FIG. 1 shows the constitution of a pushbutton used in conventional electronic equipment of this type. In FIG. 1, the electronic equipment on which the pushbutton is mounted includes a pushbutton 103 which has a manipulation surface 103a thereof projected from a button hole 102 formed in a face panel 101; a chassis 104 which has a guide portion 104a which slidably guides an angled cylindrical barrel portion 103b of the pushbutton 103, a board 106 which is fixed to the chassis 104 by mounting screws 105, a rubber contact switch 107 which is mounted on the board 106 and operated when a distal end portion of the barrel portion 103b of the pushbutton 103 pushes the rubber contact switch 107, and an LED (light emitting diode) 108 which is mounted on a circuit of the board 106. The LED 108 is arranged between a pair of fixed contacts 107b of the rubber contact switch 107. When an operator pushes the manipulation surface 103a of the pushbutton 103, movable contacts 107a of the rubber contact switch 107 are pushed by the distal end portion of the barrel portion 103b and hence, the movable contacts 107a are brought into contact with and become conductive with the fixed contacts 107b on the board 106 whereby given functional portions are operated and, at the same time, the LED 108 is lit or turned on and letters and symbols formed on an illumination portion 103b on the manipulation surface 103a of the pushbutton 103 are illuminated.
A task to be solved with respect to the electronic equipment provided with such a pushbutton is the alignment of an axis of the guide portion 104a of the chassis 104 and an axis of the button hole 102 formed in the face panel 101. When these axes are not aligned with each other due to a dimensional error or a mounting error, the manipulation surface 103a of the pushbutton 103 does not accurately project from the button hole 102 formed in the face panel 101. That is, there may be a case that the manipulation surface 103a is caught by a periphery of the button hole 102 leading to a defective operation. Further, in a worst case, it is impossible to make the pushbutton 103 project from the button hole 102. In view of the above drawbacks, conventionally, there has been known the structure in which an intermediate member is arranged between the pushbutton 103 and the chassis 104 and play is formed between the pushbutton 103 and the intermediate member, whereby irregularities of the dimensional error or the mounting error can be absorbed by the play (for example, Japanese Unexamined Utility Model Publication No. Sho 59-69439 (pages 3 to 6, FIG. 2)).
However, in the abovementioned conventional structure which absorbs the irregularities of the dimensional error or the mounting error, the pushbutton has play and hence, there have been drawbacks that the pushbutton tilts in a pushbutton hole, the pushbutton generates weird noise, and the manipulation feeling is poor. Particularly, when the face panel is made of wood, it is difficult to obtain the dimensional accuracy with respect to the positional accuracy of the button hole compatible to the corresponding dimensional accuracy obtainable in forming the button hole in a metal sheet or resin molded product and hence, the abovementioned drawback becomes more noticeable.
The present invention has been made to solve the abovementioned drawbacks and it is an object of the present invention to provide electronic equipment and a pushbutton to be used in such electronic equipment which can make the pushbutton accurately project from a button hole and can prevent play even when the positional accuracy of the button hole formed in a face panel is poor.
To achieve the abovementioned object, electronic equipment according to the present invention includes an outer button which has a manipulation surface which can be manipulated through a button hole formed in a panel, an inner button which is mounted inside the outer button such that the inner button is movable relative to the outer button, a chassis which has a guide portion for slidably guiding the inner button, a switch which is mounted on a board fixed to the chassis and is operated by the inner button, and positioning means which position the outer button with respect to the panel. Due to such a constitution, since the outer button is movable with respect to the inner button which is fixed to the chassis, even when the positional accuracy of the button hole formed in the panel is poor, it is possible to make the manipulation surface of the outer button accurately project through the button hole and, at the same time, it is possible to prevent play of the outer button due to the provision of the positioning means.
Further, in the electronic equipment of the present invention, the positioning means include an engaging portion which is integrally formed with the outer button and a portion to be engaged which is formed in the panel and is engageable with the engaging portion. Due to such a constitution, it is possible to easily implement the positioning means.
Further, in the electronic equipment of the present invention, the engaging portion is constituted of a pair of engaging projections which are formed on both sides of the outer button and the portion to be engaged is constituted of a pair of engaging holes which are engageable with the pair of engaging projections. Due to such a constitution, positioning of the outer button with respect to the panel can be performed without play.
Further, in the electronic equipment of the present invention, the manipulation surface of the outer button is inclined in a longitudinal direction with respect to the chassis, and, of the pair of engaging projections, the engaging projection which is away from the chassis with a shorter distance projects in a sideward direction of the outer button and the engaging projection which is away from the chassis with a longer distance projects upward from a side of the outer button. Due to such a constitution, even when the outer button is inclined in the longitudinal direction with respect to the chassis, it is possible to ensure positioning of the outer button with respect to the panel and hence, it is possible to cope with various designs of the outer buttons.
Further, in the electronic equipment of the present invention, an illumination portion is formed on the manipulation surface of the outer button, the inner button is made of a light guiding material, and a light emitting diode is arranged to face the inner button in an opposed manner. Due to such a constitution, even when the illumination portion of the outer button is arranged at a position remote from the light emitting diode, it is possible to effectively illuminate the illumination portion of the outer button through the inner button made of the light guiding material.
Further, a pushbutton according to the present invention includes an outer button which has a manipulation surface, an inner button which is mounted inside the outer button such that the inner button is movable relative to the outer button, an engaging portion which is formed on an outer side of the outer button for positioning the outer button with respect to the panel, and an engaging portion which is formed on a barrel portion of the inner button for mounting the inner button on a chassis. Due to such a constitution, in inserting the barrel portion of the inner button of the pushbutton into a guide portion of the chassis and projecting the manipulation surface of the outer button through a button hole formed in the panel, even when the positional accuracy of the button hole formed in the panel is poor, it is possible to make the manipulation surface of the outer button accurately project through the button hole formed in the panel and, at the same time, it is possible to prevent play of the outer button with respect to the panel.
As has been explained heretofore, electronic equipment according to the present invention includes an outer button which has a manipulation surface which can be manipulated through a button hole formed in a panel, an inner button which is mounted inside the outer button such that the inner button is movable relative to the outer button, a chassis which has a guide portion for slidably guiding the inner button, a switch which is mounted on a board fixed to the chassis and is operated by the inner button, and positioning means which position the outer button with respect to the panel. Accordingly, even when the positional accuracy of the button hole formed in the panel is poor, it is possible to make the manipulation surface of the outer button accurately project through the button hole and, at the same time, it is possible to prevent play of the outer button due to the provision of the positioning means.